Adding a year ribbon to thumbnails with PHP and GD

listing.html

<div class="film">
	<div class="imgbox">
		<div style="background-image: url(ribbon.php?text=2010)" class="year">
		</div>
		<img height="151" width="200" alt="In tellus" src="robot1.gif" />
	</div>
	<h4><a href="/in-tellus-libero">In tellus libero</a></h4>
	<p>In tellus libero, pretium et rhoncus ut, fringilla et enim. Duis at dolor non dolor ultricies…</p>
</div>

ribbon.php

<?php //make sure there is no whitespace echoed or it will cause an error!

//Usage: Use this file as the src for an <img> tag or a CSS background image. 
// <img src='ribbon.php?text=1985' />
// .ribbon { background-image: url(ribbon.php?text=1985); }

//we're making a transparent PNG
header("Content-type: image/png");

//Load in the ribbon image
$im=imagecreatefrompng("ribbon.png");

//The background color is pink
$bg_color = imagecolorallocate($im, 255, 162, 144);

//Set pink as transparent in this image
imagecolortransparent($im,$bg_color);

//Text color is white
$text_color = imagecolorallocate($im, 255, 255, 255);

//To use Arial, we have to include arial.ttf. You can find it in your fonts directory.
//The text that we're outputting is from the query string.
imagettftext($im, 14, 45, 30, 60, $text_color, 'arial.ttf', $_GET['text']);

//Output the image
imagepng($im);

//Cleanup
imagedestroy($im);

//Let's leave out the end-php tag so we don't end up with accidental whitespace!

style.css

/* This contains an image and the ribbon */
.imgbox {
	float: left;
	height: 152px;
	margin-right: 24px;
	overflow: hidden;
	position: relative;
	text-align: center;
	width: 202px;
}
/* This is the ribbon */
.imgbox .year {
	bottom: 0;
	height: 63px;
	position: absolute;
	right: 0;
	width: 108px;
	background: transparent;
	background-position: bottom right;
}

I know this is possible with CSS3, but with GD the result is cleaner (doesn't wiggle when you hover over it), and automatically consistent cross-browser.

Why not modify the actual image and save a copy of it instead of creating it every time?

good idea.